Couples tend to look like each other. Some people seem to look a lot like their pets. Such observations are a common source of jokes and jibes but inside them lie an important truth: Our brains prefer the familiar.

Statistically you are most likely to choose partners who look a lot like you. They'll also share your tastes and values. However much you may pride yourself on being wild and eclectic, each of us represents a pattern that some other people quite closely approximate, and these are the people we tend to like. Our brains are very similar to Amazon's recommendation engine or eHarmony's dating profiler.

The reason for this is familiar information is prioritized by our brains. Known information doesn't need to be considered or scrutinized so it reaches our consciousness more quickly. This is highly efficient, a form of load balancing. We deal with the easy stuff first.

But what is most familiar to you? You. You are the voice you hear in the morning, the face you see in the mirror. So the most familiar information you absorb is information about yourself. What that means is that when you encounter someone very like yourself, that person gets priority too. We call it 'liking' but in some respects, it is just putting people similar to ourselves into a priority lane.

This is how bias works—not as conscious discrimination but as a physiological preference for what is already known. That is why, despite billions of dollars spent on diversity programs, it has proven so hard to get major corporations to significantly increase their representation of women and minorities in senior positions. Biases like this aren't conscious.

Why does this matter to your business? Because it means that, however funky, creative, and imaginative you may be, you are most likely to seek out others just like you. And once you've gathered all those wild and wonderful people together, there's a significant likelihood you will all have very similar thoughts, views, life experiences, and attitudes. In other words, you'll be quite homogenous and probably get along very well. You will like this because it is comfortable.

But it's also dangerous. The company in which there is no conflict is the one where there's no debate and precious little thinking. The reason you need people not like you is because they will spark argument and dissent. Because they don't share your worldview, their ability to spot risks or greater opportunities is immensely valuable. You need to find these people, cherish them—and not turn them into clones.

It's human nature—and human biology—to gravitate toward people like yourself and to enjoy the harmony that that engenders. Finding and getting along with people very different from you is hard work and requires a significant investment of time. But think of this as your insurance policy. You need lots of extra pairs of eyes and ears—and you need them to see and hear things that you can't. Otherwise, as you all look together in one direction, you'll miss the huge hulking opportunity that lurks in the blind spot just outside your line of vision. What you can't see will hurt you.